When.com Web Search

Search results

1. Results From The WOW.Com Content Network

2. Lumen (unit) - Wikipedia

   en.wikipedia.org/wiki/Lumen_(unit)

   The lumen (symbol: lm) is the unit of luminous flux, a measure of the perceived power of visible light emitted by a source, in the International System of Units (SI). Luminous flux differs from power ( radiant flux ), which encompasses all electromagnetic waves emitted, including non-visible ones such as thermal radiation ( infrared ).

3. Orders of magnitude (illuminance) - Wikipedia

   en.wikipedia.org/wiki/Orders_of_magnitude...

   1 lux < 1 lux: Extreme of darkest storm clouds, sunset or sunrise 10 1: 1 decalux: 40 lux: Fully overcast, sunset or sunrise 10 2: 1 hectolux < 200 lux: Extreme of darkest storm clouds, midday 400 lux: Sunrise or sunset on a clear day (ambient illumination) 10 4: 10 kilolux: 10–25 kilolux: Typical overcast day, midday 20 kilolux

4. Luminous flux - Wikipedia

   en.wikipedia.org/wiki/Luminous_flux

   Luminous flux (in lumens) is a measure of the total amount of light a lamp puts out. The luminous intensity (in candelas) is a measure of how bright the beam in a particular direction is. If a lamp has a 1 lumen bulb and the optics of the lamp are set up to focus the light evenly into a 1 steradian beam, then the beam would have a luminous ...

5. Lux - Wikipedia

   en.wikipedia.org/wiki/Lux

   The lux (symbol: lx) is the unit of illuminance, or luminous flux per unit area, in the International System of Units (SI). [1] [2] It is equal to one lumen per square metre.In photometry, this is used as a measure of the irradiance, as perceived by the spectrally unequally responding human eye, of light that hits or passes through a surface.

6. Luminous efficacy - Wikipedia

   en.wikipedia.org/wiki/Luminous_efficacy

   lux (= lumen per square metre) lx (= lm/m 2) L −2 ⋅J: Luminous flux incident on a surface Luminous exitance, luminous emittance M v: lumen per square metre lm/m 2: L −2 ⋅J: Luminous flux emitted from a surface Luminous exposure: H v: lux second: lx⋅s L −2 ⋅T⋅J: Time-integrated illuminance Luminous energy density ω v: lumen ...

7. Fluorescent-lamp formats - Wikipedia

   en.wikipedia.org/wiki/Fluorescent-lamp_formats

   High-lumen retrofit lamps for 40W T12 lamps in North America. Popular tube diameter in Japan; Circular 32W and 40W T10 lamps (Older versions of the 32W and 40W T9 lamps) T12 T38 1 + 1 ⁄ 2: 38.1 G13 bi-pin; Fa8 single-pin; R17d recessed double contact; One of the first diameters of fluorescent lamps, with the 15W T12 and 20W T12 having been ...